Fill container with water. As water drips through copper
rings, metal canisters become polarized (to see why, check out this link:
Kelvin's Thunderstorm).
Bend copper arms so that the thin conducting wires (attached to each arm)
are close together but not touching. After 10 or 20 seconds of drip time touch
the two conducting wires together using a non-conducting rod (pencil), little
light bulb should blink at the moment of contact.

Tricks to making it work: Make sure base is dry (to keep
canisters electrically isolated); position copper rings at a location that
is just below where the water stream breaks apart into droplets; hold a charged
object (i.e. charged nylon rod) close to one of the copper rings as the water
is dripping to get the charge separtation process started.